Table 1.

Optimization of the Pd-catalyzed C(sp²)–H alkylation of benzene.

Entry	Variation from standard conditions	Yielda (%)
1	No deviation	76
2	Pd(PPh3)2Cl2 instead of Pd(PPh3)4	74
3	Pd(OAc)2/PPh3 (1:4) instead of Pd(PPh3)4	71
4	Pd(PPh3)2Cl2/XantPhos (1:1.2) instead of Pd(PPh3)4	52
5	Pd(PPh3)4/DPEPhos (1:1.2) instead of Pd(PPh3)4	28
6	KOAc instead of KHCO2	74
7	K2CO3 instead of KHCO2	32
8	KHMDS instead of KHCO2	44
9	25 °C with fan cooling	27
10	With CyCl instead of CyBr	10
11	With CyI instead of CyBr	5
12	2.5 mol% of Pd(PPh3)4	82 (80b)
13	1 mol% of Pd(PPh3)4	47
14	At 100 °C, in the absence of light irradiation	0
15	Without Pd(PPh3)4 or KHCO2 or light irradiation	0

Reaction conditions: 2a (0.1 mmol, 0.033 M), Pd(PPh₃)₄ (5 mol%), KHCO₂ (2 equiv), and benzene (3 mL) under 40 W blue LED irradiation without fan cooling (50 ± 5 °C).

^aGC yields using dodecane as an internal standard.

^bIsolated yield.